Slicing machine including knife sharpening means



May 11, 1965 w. ENG] 3,182,700

SLICING MACHINE INCLUDING KNIFE SHARPENING MEANS Filed March 8, 1962 I 4 Sheets-Sheet 1 lOa 1N VEN TOR.

4 0//Pr BY May 1 .1, 1965 W. ENGI SLICING MACHINE INCLUDING KNIFE SHARPENING MEANS Fil edx March 8, 19s

4 Sheets-Sheet 2 [N VEN TOR.

SLICING MACHINE INCLUDING KNIFE SHARPENING MEANS Filed March 8, 1962 W. ENGI May 11, 1965 4 Sheets-Sheet 3 Fig. I2

v INVENTOR.

4/9/14 in) BY Fig. I!

May 11, 1965 w. ENG! SLICING MACHINE INCLUDING KNIFE SHARPENI NG MEANS 4 Sheets-Sheet 4 Filed March 8, 1962 1N VEN T OR.

3,182,700 SLICING MACHINE INCLUDING KNIFE SHARPENING MEANS Walter Engi, Zurich, Switzerland, assignor to Adolf Ditting Filed Mar. 8, 1962, Ser. No. 178,387 Claims priority, applicatziogn s/vgiltzerland, Mar. 13, 1961,

Claims. or. 146-102) This invention relates to a slicing machine and more particularly to a sharpening device for the circular knife of a slicing machine.

It is a first object of thepresent invention to provide means for simplifying the sharpening operation of the circular knives of a slicing machine and to facilitate the operation to the point that it is substantially indepen- .thesharpening operation the operator needs not place his hands directly into the region of the knife.

It is a further object. of the invention to provide means affording a compact and simple sharpening device of the nature referred to, which may be operated and cleaned with great ease. 1

These and other objects of the invention will become apparent 'froin the following description, taken in connection with the accompanying drawing, in which:

FIGURE 1 is a side view of a slicing machine with a sharpening device, according the invention,

FIGURE 2 is a plan view from above of the machine of FIGURE 1,

FIGURE 3 is a sectional plan view taken along the line III-III of FIGURE 1, i

FIGURE 4 is an end view, partly in section and taken in the direction of the arrow E in FIGURE 2, of the sharpening device,

FIGURE 5 is a sectional .plan view of the sharpening device and the drawing-off disc, taken along the line VV of FIGURE 4.

- FIGURE 6 is a. sectional plan view of the sharpening device and thedrawing-olf disc taken along the line VIVI of FIGURE'4,

FIGURE 7 isa sectional plan view of the drawingoff disc showing it in an inoperative position relative to the circular knife,

FIGURE 8 is a sectional plan view of the sharpening disc showing it in an inoperative position relative to the circular knife,

FIGURE 9 is a sectional plan view similar to FIG- 'URE 7 but showing the drawing-off disc shortly before a sharpening operation,

FIGURE 10 is a sectional plan view similar to FIG- URE 8 but showing the sharpening disctshortly before a sharpening operation,

FIGURE 11 is a sectional plan view similar to FIG URES 7 and 9 but showing the drawing-off disc during sharpening of the knife of the slicing machine,

FIGURE 12 is a sectional plan view similar to FIG- URES 8 and 10 but showing the sharpening disc during sharpening of the knife of the slicing machine,

FIGURE 13 is a .side view of part of a slicing machine showing a modified form of a sharpening device,

FIGURE 14 is an end view of the modified form of sharpening device of FIGURE 13, the view being taken in the direction of arrow G in FIG. 13, and

United States Patent 0 3,182,706) Patented May 11, 1965 ice FIGURE 15 is a sectional plan view of the drawing-off disc, similar to that of FIGURE 9 but drawn to a larger scale.

Referring first to FIGURES 1 and 2, the slicing machine shown therein is motor-driven and can-be used for slicing meat, sausage and other materials. The machine has a vertical blade or circular knife 1 and a horizontal, rectilinearly displaceable table 2 or feed carriage for carrying the material to be cut. An abutment plate 3 or regulating tray adjustable relative to the knife 1 in the direction of the double arrow M serves for adjusting the slice-thickness to be cut off the material. This adjustment is effected by means of a rotary knob 4 which also carries a switch 5 for the motor (not shown) driving the circular knife 1. The abutment plate 3 is adjustable in such manner that the radial spacing a between the knife 1 and the abutment plate 3 can be regulated and kept substantially constant, at approximately even though the diameter of the knife 1 gradually becomes smaller due to sharpening operations.

The table 2 is mounted in such manner as to be easily reciprocated on rails (not shown) in the direction of the double arrow K (FIGURE 2) and has on the operating side a vertical part or face 211 which projects vertically beyond the material-abutment plate 3 and against which the material to be cut is pressed by hand.

Arranged on the underside of the material-carrying table 2, near the abutment 2a, is a transverse strip '7 extending over the entire width of the table 2 at right angles to the plane of the knife 1 and against which bears a fiat slide member 8 retained displaceably by means of a cover plate 9 removably secured on the table 2. The slide member 8 has, as shown in' FIG- URE 3 on its end face adjacent the knife 1, a projection 8a which extends beyond the abutment 2a and on which the housing 10 of the sharpening device 11 is secured by screws 56. The slide member 8 can be rectilinearly displaced perpendicularly to the direction of travel of the table 2 by hand by means of apivotal bent over lever 14 mountedon a pivot 19. The lever 14 carries at its end cont-acting the slide member 8 a roller 15 eta-operating with that end face of the slide member 8 which is nearest the pivot 19.

In the inoperative position of the slide member 8, the bent-over lever 14 is in the position shown in full lines in FIGURE 3, the slide member 8 being pressed towards the side of the machine remote from the knife 1 by means of a compression spring 16 mounted in a slot 17 in which ,a stationary pressed-in pin 18 is positioned. When the lever 14 is pivoted about the pin 19, which is also pressed into the cover plate 9, the roller 15 presses the slide member 8 in the direction of the arrow P against the knife 1. In this working position of the angle lever 14, shown in dot-dash lines in FIGURE 3, the axis of the in 19 and the axis of the roller 15 are positioned approximately in aplane parallel to the longitudinal axis of the slide member 8, i.e. the lever 14 is in a dead-centre position or slightly beyond it. By this means, the slide member 8 is prevented from returning automatically into its inoperative position under the action of the spring 16, after the lever 14 has been released.

The sharpening device proper has two sharpening members, i.e. an upper abrasive disc 25 shown in FIGURE 5, which is called a drawing-off disc, and a lower abrasive disc 26, shown in FIGURE 6, which is called a sharpening disc. The pivoting axes of these two discs extend both approximately horizontally and enclose an angle relative to each other, substantially equal to the taper angle of the edge of the knife.

The drawing-off disc 25 is rotatably mounted in the housing 10 and is axially displaceable with respect thereto. The disc 25 is secured by means of a nut 31 on a sleeve 3t), a central guide pin 32 of the sleeve 39 being received in a hollow pivot 29. The hollow pivot 29 is screwed into the housing and is secured by means of a lock nut 56. The axis of the pivot 29 is parallel or substantially parallel to the axis of the knife 1. Between the sleeve 3! and the pivot 29 is an annular hollow space 33 receiving a compression spring 34 which surrounds the pivot 29 and which bears on the bottom of the hollow space 33 and also on the housing 10 to press the drawing-off disc in the direction of arrow A. As shown in FIGURE 5, the tip 27 of the sleeve bears against a leaf spring 23 secured on the housing 19. The strength of the spring 28 is greater than that of the spring 34.

The rotatably mounted sharpening disc 26 shown in FIGURE 6 is also secured on a sleeve 35 by means of a nut 36. A guide pin 37 of the sleeve 35 is mounted for axial displacement and pivoting movement in a hollow pivot 38 secured in the housing 10 by means of a lock nut, the pivot 38 being intersected by the plane of the cutting edge of the knife 1. The axes of the sleeve 35 and pivot 38 extend at an angle of between 16-30, preferably 23, relatively to the main plane 68 of the knife 1. The hollow pivot 38' has, at its free lower end, a radial projection 40 against which one end of a compression spring 41 bears. The spring 41 surrounds the pivot 38 and is disposed in a radial recess 43 between the sleeve 35 and the pivot 38. The other end of the spring 41 bears against a resilient securing ring 42 inserted in the radial recess 43. The spring 41 presses the sharpening disc 26 in the direction of arrow B. In the inoperative position, the end of face of the hollow pivot 38 bears on the bottom of the bore of the sleeve 35. A tip 44 of the sleeve 35 contacts the leaf spring 28 in the same manner as the tip 27 of the sleeve 30 of the drawing-off disc 25.

The housing 10 is closed relative to the abutment plate 3 by means of a cover plate 46. In the upper side of the 'housing 19, however, there is an aperture 55 directed towards the knife 1, in order that the knife 1, during a sharpening process, may enter into the interior of the housing 10 and there contact the two abrasive discs 25 and 26. This aperture 55 (FIG. 2) can be covered over by a slide member or a hood.

On the side of the cover plate 46 of the sharpening disc housing 10 there is carried an abutment pin 50 which is intended to engage in a groove 51 in the abutment plate 3, so as to engage a pin 52 (FIGURE 15) when an end position has been reached during a sharpening operation.

This pin 52 could also be mounted on the member 8.

In order that reciprocal movement of the table 2 either for cutting material or for sharpening the knife, is possible only in the two end positions of the slide member 8, but not in intermediate positions-which could result in damage to the knife 1 or to the sharpening device 11- safety arrangements can be made for example by providing for the engagement of a pin secured on the slide member 8 in grooves formed in a stationary part of the machine.

In a modified form shown in FIGURES l3 and 14, in place of the slide member 8 with the hand lever 14 and the associated components, the sharpening disc housing 10 is mounted for pivoting movement about a pin 58 on a horizontal or substantially horizontal pivot axis. The pin 58 is disposed on the upper portion of the vertical face 2a. In this unilaterally open housing 10 are disposed the drawing-off disc 25 and the. sharpening disc 26 each of which is rotatably mounted in bearing eye pieces 60. The mountings being substantially the same as those shown and described in FIGURES 5 and 6. The two discs 25, 26 are supported at one of their ends by a common resiliently yielding leaf spring 23, so that an axial movement of the disc 26 is also transmitted to the disc 25. The spring 28 is rigidly secured by a screw 61 to the base of the housing 10. In order to retain the housing 10 either in the working position, as shown in full lines in IGURE 14, or in the inoperative position, as shown 4 in broken lines in FIGURE 14, there is a locking pin 62 which can be inserted as desired in anaperture 63 or 64, thus retaining the housing 10 in the position required in each specific case.

In further modifications, not shown, the housing 10 could be pivotal about a vertical or oblique axis.

The operation of the sharpening device of FIGURES l to 6 and 15 is described hereinbelow with reference to FIGURES 7 to 12.

The table 2 carrying the material to be cut is first of all withdrawn to its rearmost position, near the rotary knob 4, so that the housing 10 is out of range of the circular knife 1, whereby the drawing-off disc 25 and the sharpening disc 26 take the positions relative to the knife 1 shown in FIGURES 7 and 8 respectively. The abutment plate 3 is then displaced by means of the rotary knob 4 into its outermost position farthest from the knife 1 (shown in dot-dash lines in FIGURE 2). After the machine has been prepared to this extent, the sharpening device 11 can be displaced in the direction of the arrow C, this being effected by pivoting the lever 14. The drawing-oif and sharpening discs 25, 26 are, as this is done, still in their inoperative position and there is a spacing b (FIGURES 9 and 15) of approximately between the knife surface and the end face of the drawing-off disc 25.

Due to the adjustment of the slide member 8 in the direction of the arrow P, the abutment pin 50 enters into the groove 51 in the abutment plate 3. i

The spacing a, (FIG. 2) between the knife 1 and the plate 3 must be kept approximately constant by periodic regulation of the abutment plate 3, so that the relative position of the discs 25, 26 with regard to the cutting edge of the knife 1 remains approximately constant, both when the knife 1 is new and when it is worn and its diameter is therefore smaller.

When the table 2 for carrying the material is now displaced by hand in the direction of the arrow D (FIG- URES 9 and 10) the sharpening device 11 approaches the knife 1 which first of all contacts the obliquely extending sharpening disc 26. The disc 26 now sharpens the cutting edge of the knife 1. The table 2 is then pushed slightly further until the abutment pin 50 of the housing 10 bears against the pin 52 of the abutment plate 3. During this movement, (the knife 1 presses the tip 44 of the spindle of the sharpening disc 26 against the leaf spring 28 which is thus pressed in the direction of arrow A. Due to this movement of the leaf spring 28, the drawing-off disc 25, the spindle of which also bears against the same leaf spring, is caused to bear against the main plane 68 of the knife, i.e. the spacing b previously adjusted between the drawing-off disc 25 and the knife 1 is taken up and the drawing-off disc 25 engages the knife and removes from the knife 1 the wire edge or burr formed thereon by disc 26 during the sharpening process.

After the knife 1 has been sharpened and de-burred in this manner, the table 2 is drawn back into its original position by hand and the discs 25 and 26 return to their rest positions under the force of the leaf spring 28. The lever 14 is then pivoted back, so that the slide member 8 and therewith the sharpening device 11 is moved back by the spring 16 into the original inoperative position illustrated in FIGURE 3. The spring 16 is stronger than the spring 41 and the leaf spring 28 together, in order that the slide member 8 may not be moved, during the sharpening process, towards the knife 1.

In the modified form shown in FIGURES 13 and 14, and wherein the parts corresponding to those of the previous modification bear the same numbers with a suffix a, the fundamental mode of operation is the same as that of the form shown in FIGURES 7 to 12. However, in place of the rectilinear displacement of the sharpening device 11a within and externally of the zone of the knife 1a, in the form of FIGURES 13 and 14, the housing. 10a is pivoted about the pin 58 as a horizontal pivot.

It will be appreciated that in the various forms of sharpening device 28 described above, the leaf spring 28 and/ or the housing connect the sharpening and drawing-off discs together in such manner that a movement of the sharpening disc approximately in the direction of its axis brings about a movement, dependent thereon, of the drawing-off disc transversely of the plane of the cutting edge of the knife.

In a contemplated modification of the sharpening device, the tips 27 and 44 of the spindles of the discs 25 and 26 could bear against a fixed abutment on the cover plate 46 and thus be non-axially displaceable. The compression spring 41 of the sharpening disc 26 is then made somewhat stronger than the compression spring 16 of the slide member 8. During the sharpening of the knife 1, the slide member 8 is then pushed under the action of the obliquely positioned sharpening disc 26 in the direction of the arrow P towards the knife 1 until the drawingolf disc 25 contacts the knife and removes from it the Wire edge. lin this modification, the springs 34 and 41 are dispensed with.

The sharpening device 11 could be removably secured on the table 2 carrying the material to be cut.

In a gravity feed type of the machine the cutting knife 1 andtherewith also the table 2 carrying the material could be arranged in an oblique position (for example 45 relatively to the horizontal).

Various changes and modifications may be made without departing from the spirit and scope of the present invention and it is intended that such obvious changes and modifications be embraced by the annexed claims.

Having thus described the invention, what is claimed as new and what is desired to be secured by Letters Patent 1s:

1. A slicing machine, comprising a cutting mechanism with a circular rotary knife having an axis of rotation, reciprocable table means for guiding the object to be sliced by said knife and movable in a direction substantially at right angles to the axis of rotation of said knife, sharpening means carried by said table means in a radial direction from said knife, said sharpening means comprising a first abrasive disc and a second abrasive disc for sharpening the knife, axle means rotatably supporting said first disc on an axis substantially parallel to the axis of said knife, axle means rotatably supporting said second disc on an axis inclined relative to the axis of said first disc and offset therefrom in the direction of the circumference of said knife, each disc being reciprocable along its respective axis, first and second means connected to said first and second discs respectively and exposed for engagement, a common biasing member engaging said first and second means biasing said discs in one direction, first spring means engaging said first disc and biasing it in a direction opposite to said one direction and weaker than said biasing member, and second spring means engaging said second disc and biasing it in said one direction, said discs as to the positions thereon nearest the knife being positioned one on one side of the plane of the edge of the knife and the other on the other side of said plane.

2. A slicing machine according to claim 1, in which said common biasing member is a leaf spring, a housing for said discs and supporting said axle means, said leaf spring being fixed to said housing.

3. In a slicing machine; a circular rotary knife, and sharpening means for the knife comprising a first abrasive disc and a second abrasive disc, at least the portions of said first and second abrasive discs nearest the knife being disposed on opposite side of the plane of the edge said knife, the axis of said first disc being substantially parallel to the axis of said knife, the axis of said second disc being inclined to the axis of the first disc and offset from the axis of first disc in the direction of the circumference of said knife, spindles on which said abrasive discs are rotatably mounted, means for moving said discs axially on said spindles to bring said abrasive discs into and out of engagement with the edge of said knife, means connecting said discs whereby the movement of one of said discs axially causes movement of the other of said discs axially to thereby cause said other disc to clear from the knife the burr formed thereon by the said one disc during a sharpening process.

4. A slicing machine, comprising a circular rotary knife with a cutting edge, said knife having an axis of rotation, a reciprocable movable carriage for carrying the articles to be sliced, a support on said carriage rotatably supporting a first and a second grinding disc for sharpening the knife, said support being movably mounted on said carriage for movement of said support into a working position wherein said discs are substantially in the plane of said knife or into a retracted position wherein the discs are disposed out of the plane of said knife, the axis of said first disc being substantially parallel to the axis of said knife, the axis of said second disc being inclined relative to the axis of said first disc and offset therefrom in the peripheral direction of said knife, at least those parts of said first and second grinding discs nearest said knife being disposed on respectively opposite sides of the plane of the cutting edge of said knife, spindles on which said discs are respectively mounted? a biasing member engaging said spindles and urging said discs in a common axial direction, said direction being such that the second disc is urged toward the knife and will engage the knife while the first disc is spaced from the knife, and means biasing said first disc toward the knife with a thrust less than that of said biasing member whereby movement of said biasing member brought about by movement of said second disc by the knife as a result of movement of said carriage toward said knife will bring about movement of said first disc into engagement with the knife to thereby clear the knife of the burr formed thereon by said second disc during the sharpening process.

5. A slicing machine according to claim 4, comprising stop means for limiting the movement of the carriage in the direction toward said knife during the sharpening of the knife.

References Cited by the Examiner UNITED STATES PATENTS 9/31 Van Berkel. 4/5 3 Klingens.

J. SPENCER OVERHOLSER, Primary Examiner, 

1. A SLICING MACHINE, COMPRISING A CUTTING MECHANISM WITH A CIRCULAR ROTARY KNIFE HAVING AN AXIS OF ROTATION, RECIPROCABLE TABLE MEANS FOR GUIDING THE OBJECT TO BE SLICED BY THE KNIFE AND MOVABLE IN A DIRECTION SUBSTANTIALLY AT RIGHT ANGLES TO THE AXIS OF ROTATION OF SAID KNIFE, SHARPENING MEANS CARRIED BY SAID TABLE MEANS IN A RADIAL DIRECTION FROM SAID KNIFE, SAID SHARPENING MEANS COMPRISING A FIRST ABRASIVE DISC AND A SECOND ABRASIVE DISC FOR SHARPENING THE KNIFE, AXLE MEANS ROTATABLY SUPPORTING SAID FIRST DISC ON AN AXIS SUBSTANTIALLY PARALLEL TO THE AXIS OF SAID KNIFE, AXLE MEANS ROTATABLY SUPPORTING SAID SECOND DISC ON AN AXIS INCLINED RELATIVE TO THE AXIS OF SAID FIRST DISC AND OFFSET THEREFROM IN THE DIRECTION OF THE CIRCUMFERENCE OF SAID KNIFE, EACH DISC BEING RECIPROCABLE ALONG ITS RESPECTIVE AXIS, FIRST AND SECOND MEANS CONNECTED TO SAID FIRST AND SECOND DISCS RESPECTIVELY AND EXPOSED FOR ENGAGEMENT, A COMMON BIASING MEMBER ENGAGING SAID FIRST AND SECOND MEANS BIASING SAID DISCS IN ONE DIRECTION, FIRST SPRING MEANS ENGAGING SAID FIRST DISC AND BIASING IT IN A DIRECTION OPPOSITE TO SAID ONE DIRECTION AND WEAKER THAN SAID BIASING MEMBER, AND SECOND SPRING MEANS ENGAGING SAID SECOND DISC AND BIASING IT IN SAID ONE DIRECTION, SAID DISCS AS TO THE POSITIONS THEREON NEAREST THE KNIFE BEING POSITIONED ONE ON ONE SIDE OF THE PLANE OF THE EDGE OF THE KNIFE AND THE OTHER ON THE OTHER SIDE OF SAID PLANE. 